Hola! BCN Travel cards offer 2-5 days unlimited travel on consecutive days on the city's metro, bus, tram, FGC and RENFE suburban train lines, as well as on the airport train.
The T-mobilitat digital tickets using contactless technologys offers the T-Casual card, good for 10 journeys in Zone 1 for €12.15 and the T-Usual Card good for a month’s travel for €21.35 that you can recharge.
If you plan to visit many of the attractions included in the Barcelona Card, however, it could offer the better deal—it's worth comparing the two. Also check out TMB's Bus Turístic, which makes it easy to take in the city's main sights.
Image by Francesc_2000